Synthetic peptide compositions with immunoreactivities to antibodies to HTLV

ABSTRACT

The present invention relates to a method for the detection HTLV-I and/or HTLV-II reactive antibodies and diagnosis of ATL (adult T cell leukemia/lymphoma) condition by the use of chemically synthesized peptide compositions. The peptide compositions comprise peptides having amino acid sequences corresponding to transmembrane and external segments of the envelope protein of HTLV-I/HTLV-II and mixtures thereof. The peptide compositions are highly immunoreactive with antibodies to HTLV in sera. The present invention further relates to a method for the simultaneous detection and diagnosis of ATL, HTLV-I and/or HTLV-II infection and Acquired Immune Deficiency Syndrome (AIDS) by the use of chemically synthesized HTLV peptide compositions in conjunction with a chemically synthesized HIV (1 and 2) peptide composition. The present invention also provides a simple method to differentiate between HTLV-I and HTLV-II infections. 
     The detection method includes an enzyme-linked immunosorbent assay (ELISA), an immunoradiometric assay (IRMA), and other forms of immunoassay procedures such as enzyme immuno blotting assay on nitrocellulose paper and an agglutination assay using the peptide composition as the antigen. The preferred detection method is ELISA.

This Application is a divisional of 07/901,874, filed Jun. 22, 1992, nowU.S. Pat. No. 5,476,765, which is a continuation-in-part of ApplicationSer. No. 07/469,291, filed Jan. 24, 1990, which is continuation-in-partof Application Ser. No. 07/297,635, filed Jan. 13, 1989, now abandonedwhich is in turn a continuation-in-part application of Application Ser.No. 07/001,885, filed Jan. 9, 1987, which has now issued a U.S. Pat. No.4,833,071 in May 23, 1989.

Human T-cell leukemia viruses have been linked to certain adult lymphoidmalignancies, notably adult T-cell leukemia-lymphoma (ATL) and hairycell leukemia (HCL) (1-3, 24 and 25). There are two recognizedsubgroups, HTLV-I and HTLV-II. Up to the present, much of the work isdirected to HTLV-I prevalent in ATL patients in Japan. However, recentstudies show that the HTLV-II is more prevalent in the intravenous drugusers in the metropolitan areas of U.S.A. (27, 28). Antibodies thatreact with HTLV proteins have been found in sera of ATL patients. TheseHTLV antibodies recognize both the gag core antigens and the envelopeproteins of the viruses (4, 5, 27). Human Immunodeficiency Virus (HIV)is a retrovirus causatively linked to Acquired Immune DeficiencySyndrome (AIDS) and AIDS related complex (ARC). Antibodies that reactwith HIV proteins have been found in the sera of AIDS and ARC patients.These HIV antibodies recognize both the gag core antigens and envelopeproteins of the HIV virus. In the United States, the disease AIDS is farmore prevalent than ATL, with some individuals seropositive for HIV alsobeing seropositive for HTLV.

The present invention relates to highly sensitive methods for thedetection of antibodies to HTLV-I and/or HTLV-II in body fluids by theuse of synthetic peptide compositions. The present invention furtherrelates to a highly sensitive method for the simultaneous detection ofantibodies to HTLV-I, HTLV-II and HIV in body fluids by the use ofsynthetic peptide compositions. One peptide composition comprisespeptides having amino acid sequences corresponding to segments of theexternal (extracellular) portion of the HTLV-I and HTLV-II env protein,designated gp46, and may further comprise peptides having amino acidsequences corresponding to segments of the transmembrane portion of theHTLV-I/HTLV-II env protein, designated gp21. These sequences have beenfound to be highly immunoreactive to antibodies in the sera of patientswith ATL and HTL. Such peptide compositions are also useful for theproduction of a vaccine to prevent ATL or HTLV-II infection bystimulating the production of antibodies to HTLV-I/HTLV-II, whichprovide protection against HTLV-I/HTLV-II infection in healthy mammals,including humans. Furthermore, a peptide composition comprising peptideswith amino acid sequences corresponding to portions of HTLV-I/HTLV-IIenvelope proteins may be used in conjunction with a peptide compositioncomprising peptides with amino acid sequences corresponding to portionsof the MIr envelope and core proteins for the simultaneous detection ofantibodies to HTLV-I, HTLV-II and HIV.

More specifically, the present invention is directed to peptidecompositions, useful for the detection of HTLV-I and/or HTLV-IIantibodies, which comprise peptides selected from the group consistingof chemically synthesized peptides containing about thirty-four, forty,thirty-eight, twenty, twenty-four and sixteen amino acids, or theiranalogues, in a prescribed sequence; analogues, segments, mixtures,conjugates and polymers thereof. The invention is further directed tothe use of an HTLV-I and/or HTLV-II peptide composition in conjunctionwith an HIV peptide composition which comprises peptides selected fromthe group consisting of chemically synthesized peptides containing abouttwenty-one, nineteen, eleven and sixteen amino acids, sequence;analogues, segments, mixtures, conjugates and polymers thereof, for thesimultaneous detection of antibodies to HTLV-I, HTLV-II and HIV in humanbody fluids. The present invention also provides a method for diagnosingHTLV infection, HTLV-I or HTLV-II infection.

The detection methods include an enzyme-linked immunoadsorbent assay(ELISA), multi-dot, multi-line, or multi-square blotting onnitrocellulose paper, and a passive hemagglutination assay using thepeptides as the solid phase antigens. The preferred detection method isby ELISA.

Another objective is to develop an immunogen or a vaccine which, whenintroduced into healthy mammals, including humans, will stimulate oneproduction of efficacious antibodies to HHTL.

BACKGROUND OF THE INVENTION

The human T cell leukemia-lymphoma viruses (HTLV) are a family of=elated retroviruses originally isolated from patients with T celllymphoma and cutaneous manifestations. A particular subgroup of thefamily, type I, now known as HTLV-I, has been causatively linked tomalignancies which share clinical and epidemiologic features with thedisease called adult T-cell leukemia-lymphoma (ATL) which occur incertain regions of Japan (6-9), the Caribbean Basin (10,11) and thesouthwestern United States (12). There are no known enaemic areas forHTLV-II and no known casual relationship between any specific diseasewith HTLV-II. The source of HTLV-II virus introduced into theintravenous drug users is not known. Widescale seroprevalence studiesfor HTLV-II have not been carried out.

HTLV-II is structurally very similar to HTLV-I. The two viruses shareapproximately 50% sequence homology (29). HTLV-II was isolated from onepatient who had hairy cell leukemia but no casual relationship wasfound. The amino acid sequence of the env protein of HTLV-II isidentical to that of HTLV-I for 69% of the residues, and an additional14% of the amino acids represent conservative substitutions (30, 31).The X and pol genes are even more highly conserved than the env gene(32).

Because of the high degree of homology between HTLV-I and HTLV-II,standard testing assays by ELISA for HTLV-I based on whole viral lysateor recombinant proteins also cross react with HTLV-II. The peptidesdisclosed in U.S. Pat. No. 4,833,071 are also cross reactive withHTLV-II. No effective serological assay exists to distinguish betweenHTLV-I and HTLV-II env proteins although antigenic differences betweenthe two viruses have been detected by neutralization of vesicularstomatitis virus pseudotypes (5). Two supplemental methods have beenemployed to confirm that antibodies to HTLV are present in samples thatare shown to be reactive in am HTLV-I enzyme immunoassay. The WesternBlot method for HTLV-I gives bands at p15, p19, p24, p28, p32, p36 andp55 for core proteins and at gp45 and gp61 for envelope proteins (32).The radioimmuno precipitation assay (RIPA) for HTLV-I gives bands forgp45 and gp61 for env proteins, p24 and p55 for core, and p40x for the Xregion (31). Neither tests, however, distinguish between the twoviruses.

PCR has recently been used to distinguish between HTLV-I and HTLV-II.The PCR method provides definitive results (28). However, because of itsexquisite sensitivity, it is subject to false positive results.Moreover, it is a very time consuming and expensive test.

Although the mechanism of transmission of HTLV-I is currently unknown,horizontal transmission of HTLV is clearly implicated by molecular andepidemiologic analyses (13,14). HTLV seropositivity in regions endemicfor ATL is elevated overall in the general population and furtherelevated among close family members of patients and in the recipients ofblood transfusions (15,16). HTLV-II seropositivity has been identifiedin intravenous drug users in the metropolitan areas of U.S.A. (27, 28).

This means that there is an urgent need for a safe, reliable andsensitive test to screen each blood sample before its inclusion in bloodbanks and to isolate blood donations derived from HTLV-I and/or HTLV-IIinfected individuals to avoid the inadvertent spread of the virus amongpatients who must receive blood transfusions, e.g. hemophiliacs andsurgical patients.

There is an urgent need for a rapid and less expensive method todistinguish between infection with HTLV-I and HTLV-II. Since 1988,mandatory screening of all donors for HTLV-I has been performed anddonors reactive for HTLV-I, as well as HIV must be notified of theirresults. The uncertainty as to which virus, HTLV-I or HTLV-II, isresponsible for seropositivity, renders it very difficult to counsel thedonors accurately about their risk for contracting ATL or a neurologicalcomplication of HTLV-I. A method for distinguishing HTLV-I from HTLV-IIis also important for seroprevalence studies to define endemic areas forHTLV-II and pathogenicity studies for both viruses (33).

The complete nucleotide sequence of the HTLV-I virus was reported in1983 (17). This report elucidated the structure of the HTLV-I virus atboth the DNA level and the predicted protein level and permitted furtherserological studies of the different epitopes which may be present onthe HTLV-I virus. The nucleotide sequence of the HTLV-II virus wasreported in 1984, 1985 and 1986 (30, 31, 32).

Simultaneous to Seiki et al's report in 1983, Dr. Carl Saxinger atNational Cancer Institute reported that the use of the isolated HTLV-Ivirus as a solid-phase immunoadsorbent for the development of an enzymeimmunoassay for the detection of HTLV-I antibodies in the Africanpopulation (18).

It was further reported by Samuel et al. (19) that a combined cloningand expression system in E. coli has been used to identify HTLV-I DNAencoded glycoproteins which reacted immunologically with antibodies insera from ATL patients. HTLV-I DNA encoding the envelope protein wascleaved into fragments and inserted into an expression vector. Theexpression vectors were introduced into an E. coli host bytransformation. One clone, designated as pKS400, produced an envelopeprotein product found to be suitable for use as an immunoadsorbent toscreen a group of 28 coded sera. Antibodies that recognized thebacterially synthesized HTLV-I envelope protein sequences were found inall sera that had been shown to have antibodies to HTLV by an ELISAassay with disrupted virions as the antigen (18).

Slamon et al, Application No. PCT/US 85/01803, published on Mar. 27,1986 under Publication No. W086/01834, described polypeptides associatedwith immunogenic sites of HTLV-I as expression products of the X regionof HTLV-I, a highly conserved region location between env and the 3 LTRof the virus. The proteins, with a molecular weight of between 37 kd and40 kd, were cloned and expressed as fusion proteins in E. coli. Theresulting products were purified and used in liquid phaseimmunoprecipitation tests to screen sera. The results indicated anaccuracy of from about 77% to 87% (20). All of the above failed todistinguish between infection by HTLV-I or HTLV-II because of theantigens used to detect the immunoreactivity.

Synthetic peptides have been used increasingly to map antigenic orimmunogenic sites on the surface of proteins and as possible vaccines.The named inventor and a colleague previously have taken this approachto identify and characterize highly antigenic epitopes on the envelopeproteins of HTLV and to develop sensitive and specific immunoassays forthe detection of antibodies to HIV (previously designated HTLV-III)(21). See also U.S. Pat. No. 4,735,896, issued Apr. 5, 1988 and U.S.Pat. No. 4,879,212 issued Nov. 7, 1989, the contents of which are,hereby, fully incorporated by reference (22, 23). A similar approach isemployed in this invention to select and identify highly antigenicepitopes in HTLV-I and HTLV-II. In selecting regions of the envelopeprotein for epitope analysis, several strategies were employed. First,regions that exhibited a relatively high conservation of amino acidsequence between HTLV-I and HTLV-II were sought. Second, multipleoverlapping linear peptides covering whole regions of gp21, thetransmembrane portion of the HTLV envelope protein (See FIG. 1), weresynthesized and characterized. Third, multiple overlapping linearpeptides covering the whole region of gp46, the external portion of theHTLV envelope protein (See FIG. 1), were synthesized and characterized.Three peptides, from the transmembrane portion, with the followingsequences (See FIG. 2), and a mixture thereof, were found to be highlyimmunoreactive with sera from patients with ATL:

    GLDLLFWEQGGLCKALQEQC-NH2 SEQ ID NO: 1                      (I)

    QNRRGLDLLFWEQGGLCKALQEQC-NH2 SEQ ID NO: 2                  (II)

    NRRGLDLLFWEQGGLC-NH2 SEQ ID NO: 3                          (III)

and three peptides, from the external portion, with the followingsequences, and a mixture thereof, were also found to be highlyimmunoreactive with sera from patients with ATL (See FIG. 3):

    APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS-NH.sub.2 SEQ ID NO: 4   (IV)

    SSTPLLYPSLALPAPHLTLPFNWTHCFDPQIQAIVSSPCH-NH.sub.2 SEQ ID NO: 5(V)

    CFDPQIQAIVSSPCHNSLILPPFSLSPVPTLGSRSRRA-NH.sub.2 SEQ ID NO: 6(VI)

wherein:

    ______________________________________                                        A = Ala = alanine, G = Gly = glycine,                                         R = Arg = arginine,                                                                              I = Ile = isoleucine,                                      D = Asp = aspartic acid,                                                                         F = Phe = phenylalnine,                                    N = Asn = asparagine,                                                                            S = Ser = serine,                                          Q = Gln = glutamine,                                                                             W = Trp = tryptophan                                       E = Glu = glutamic acid,                                                                         Y = Tyr = tyrosine,                                        L = Leu = leucine, V = Val = valine,                                          K = Lys = lysine,  C = Cys = cysteine,                                        H = His = histidine,                                                                             P = Pro = proline                                          T = Thr = threonine                                                           ______________________________________                                    

An example of an analogue peptide corresponding to Peptide IV of HTLV-Iand found in the same region of HTLV-II contains the following sequence:

    SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS-NH.sub.2 SEQ ID NO: 10  (X)

Peptides I, II and III were described in the parent application whichhas now issued as U.S. Pat. No. 4,833,071.

Assays for antibodies to HTLV-I and/or HTLV-II based upon chemicallysynthesized peptides show several advantages over assays utilizing wholedisrupted virus or bacterially produced immunoadsorbents. The peptidescan easily be synthesized in gram quantities by using automatedsolid-phase methods, thus providing a reproducible antigen of highintegrity with consistent yields. Isolation of antigens from biologicalsystems precludes such reproducibility. More importantly, non-specificreactivities seen in non-HTLV-I or non-HTLV-II infected individuals arelikely due to the heterogeneity of the preparations used for assay. Thisis particularly true for assays using either whole virus or Escherichiacoli-derived recombinant products as immunoadsorbents. In theseprocesses, the major histocompatibility antigens or endogenous bacterialproteins of the host cells are frequently copurified with the desiredantigen virus or protein. Since antibodies to these contaminatingantigens are frequently found in normal individuals, false-positiveresults cannot be eliminated by using current antigen isolationprocesses.

The assay of the present invention thus clearly eliminates thosefalse-positive reactions encountered in the other methods and, at thesame time, shows a high sensitivity to truly positive sera by thesubstantially increased signal-to-noise ratio. This increasedsignal-to-noise ratio likely results from the purity of theimmunoadsorbent. The assay of the present invention is also highlyspecific, in that peptide IV and its HTLV-II analogue (peptide X) arealso found to be useful to distinguish between individual sera infectedwith HTLV-I or HTLV-II. That is to say, peptide IV preferentiallydetects antibodies to HTLV-I but not HTLV-II, and vice versa.

Furthermore, up to the present, no viable vaccine or method to provideprotection against HTLV-I or HTLV-II infection has been reported.Utilization of deactivated virus provokes fears of contracting thedisease, preventing its acceptability and use.

It is, therefore, an objective of the present invention to develop adetection or diagnostic procedure that does not require the use of thevirus or lysates thereof as a test reagent.

A further objective is to develop a test procedure that is highlysensitive and accurate.

A further objective is to prepare a test reagent by chemical means. Thesynthetic reagent can than be used to detect the presence of antibodiesto HTLV-I and/or HTLV-II in body fluids and diagnose ATL, therebyavoiding the danger of exposure to the virus or segments thereof and theunnecessary proliferation of the virus.

It is also an objective of the present invention to have a test reagentand procedure which can distinguish between HTLV-I and HTLV-IIinfection, to enable the medical profession to study the etiology ofHTLV-II infection, the diseases caused by the HTLV-II virus, and itseffect on the development of HIV infection in patients who are infectedwith both HIV and HTLV-II.

Another objective is to develop a vaccine which, when introduced intohealthy mammals, including humans, will stimulate production ofantibodies to HTLV-I, thereby providing protection against HTLV-Iinfection.

A further objective is to provide a non-viral immunogen which can beused in mammals for the development of monoclonal and polyclonalantibodies to HTLV-I.

REFERENCES

1. B. J. Poiesz., et al., Proc. Natl Acad. Sci. USA., 77:7415 (1980).

2. B. J. Poiesz., F. W. Ruscetti, M., S. Reitz., V. S. Kalyanaraman, R.Gallo Nature (London) 294:268 (1981).

3. R. C. Gallo et al., Proc, Nail Acad. Sci. USA., 79:5680 (1982).

4. M. Essex et al., Science 221:1061 (1983).

5. P. Clapman, K. Napy, R. A. Weiss, Proc. Natl. Acad. Sci. 81:2886(1984).

6. R. C. Gallo et al., Cancer Res., 43:3892 (1983).

7. R. C. Gallo, Cancer Surveys, L. M. Franks et al. Eds, (UniversityPress, Oxford, in press)

8. W. A. Blattner, K. Tokatsuki, R. C. Gallo, J. Am. Med. Assoc.,250:1074 (1983).

9. K. Takatsuki, J. Uchiyama, K. Sagawa, J. Yodoi, Topics in Hematology,S. Seno, F. Takaku, S. Irino, Eds. (Excerpts Medica, Amsterdam, 1977)p73.

10. W. A. Blattner et al., Int. J. Cancer, 30:257 (1982).

11. D. Catovsky et al., Lancet, 1982-I, 639 (1982).

12. D. W. Blayney et al., J. Am. Med. Assoc., 250:1048 (1983).

13. M. Robert-Guroff, F. W. Ruscetti, L. W. Posner, B. J. Poiesz, R. C.Gallo, J. Exp. Med., 154:1957 (1981).

14. R. C. Gallo et al., Proc. Natl. Acad. Sci., USA, 79:5680 (1981).

15. M. Robert-Guroff et al., J. Exp. Med., 157:248 (1983).

16. M. Shimoyama et al, Jpn. J. Clin. Oncol., 12:109 (1982).

17. M. Seiki, S. Hattori, Y. Hirayama, M. Yoshida, Proc. Natl Acad. Sci.USA, 80:3618 (1983).

18. Saxinger, C. W. et al., Science, 225:1473 (1984).

19. Samuel, K. P. et al., Science, 226, 1094-1097 (Nov. 30, 1984).

20. Slamon et al., PCT Pat. No. Publication No. W086.01834.

21 . Wang, J. J-G, Steel, S., Wisniewolski, R. and Wang, C. Y. Proc.Natl. Acad. Sci. USA, 83, pp 6159-6163 (August 1986).

22. U.S. Pat. No. 4,735,896, issued Apr. 5, 1988 to Chang Y. Wang andJames G. Wang.

23. U.S. Pat. No. 4,879,212 issued Nov. 7, 1989 to Chang Y. Wang andJames G. Wang.

24. Liu, Fu-Tong et al., Biochemistry, 18, pp. 690-697 (1979).

25. V. S. Kalyanaraman, M. G. Sarnagadharan, M. Robert-Guroff et al.,Science, 218, 571 (1982).

26. J. D. Rosenblatt et al., N. Engl. J. Med., 315:372 (1986).

27. M. Robert-Guroff, S. H. Weiss, J. H. Giron et al., J. Am Med.Assoc., 255:3133 (1986).

28. H. Lee, P. Swanson, V. S. Shorty et al., Science, 244:471 (1989).

29. R. C. Gallo, Med. Oncol. Tumor Pharmacother., 3:265 (1986).

30. K. Shimotolino, Y. Takahashi, et al., PNAS USA, 82, 3101-3105 (May1985). J. Sodroski, R. Patarca, D. Perkins et al., Science, 225:421(1984).

32. G. M. Shaw, M. A. Gonda, G. H. Flickinger et al., PNAS USA, 81:4544(1984).

33. S. G. Sandlet, C. Fang, in Transfusion-Transmitted Vital Disease,Arlington, VA:American Assn. of Blood Bankers, p. 19 (1987).

BRIEF DESCRIPTION OF THE INVENTION

According to the present invention, four additional peptides, eacharranged in a specific sequence, have been made by solid phase peptidesynthesis. These peptides have been found to be useful in a highlysensitive and accurate method for the detection of antibodies toHTLV-I/HTLV-II in sera and body fluids and in the diagnosis of ATL .Because of the high immunoreactivity, it is expected that the peptidesare also useful in stimulating production of antibodies toHTLV-I/HTLV-II in healthy mammals such as Balb/c mice.

According to the present invention, a peptide composition useful for thedetection of antibodies to HTLV-I/HTLV-II and diagnosis of ATL comprisesa peptide selected from the group of peptides comprising:

    APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS-X SEQ ID NO: 4          (IV)

    SSTPLLYPSLALPAPHLTLPFNWTHCFDPQIQAIVSSPCH-X (SEQ ID NO: 5   (V)

    CFDPQIQAIVSSPCHNSLILPPFSLSPVPTLGSRSRRA-X SEQ ID NO: 6      (VI)

    SPPLVHDSDLEHVLTPSTSWTTKILFIQLTLQS-X SEQ ID NO: 10          (X)

wherein X is --OH or --NH₂, analogues, segments, mixtures conjugates andpolymers thereof, wherein:

    ______________________________________                                        A = Ala = alanine, G = Gly = glycine,                                         R = Arg = arginine,                                                                              I = Ile = isoleucine,                                      D = Asp = aspartic acid,                                                                         F = Phe = phenylalanine,                                   N = Asn = asparginine,                                                                           S = Ser = serine,                                          Q = Gln = Glutamine,                                                                             W = Trp = tryptophan,                                      E = Glu = Glutamic acid,                                                                         Y = Tyr = tyrosine,                                        L = Leu = Leucine, V = Val = valine,                                          K = Lys = Lysine,  C = Cys = cysteine,                                        H = His = histidine                                                                              P = Pro = proline                                          T = Thr = threonine                                                           ______________________________________                                    

The highly sensitive and accurate method of detecting antibodies toHTLV-I/HTLV-II in body fluids and diagnosis of ATL comprises thefollowing steps:

A. Preparing peptides composition comprising a peptide selected from thegroup having the following amino acid sequences:

    APPLLPHSNLDHILEPSIPKWKSKLLTLVQLTLQS-X SEQ ID NO: 4         (IV)

    SSTPLLYPSLALPAPHLTLPFNWTHCFDPQIQAIVSSPCH-X SEQ ID NO: 5    (V)

    CFDPQIQAIVSSPCHNSLILPPFSLSPVPTLGSRSRRA-X SEQ ID NO: 6      (VI)

    SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS-X SEQ ID NO: 10         (X)

wherein X is --OH or NH₂, analogues, segments, mixtures, conjugates andpolymers thereof; and

B. Using about 0.01 ug to about 20 ug per test in a buffer at a pH ofabout 7 to 10, of the peptide composition as the antigen in animmunoassay procedure.

Further, according to the present invention, the peptides by themselves,or when coupled to a protein or a polymer carrier, or when polymerizedto homo or hereto dimers or higher oligomers by cystsine oxidation,induced disulfide cross linking reagents, or when directly synthesizedonto a polyvalent lysine resin, can be used to stimulate production ofantibodies to HTLV-I and/or HTLV-II in healthy mammals, includinghumans. The method comprises introducing an effective amount of thepeptide composition including a mixture of these six peptides,conjugated to a carrier, such as human serum albumin, or as a polymer,into the body of a healthy mammal by intraperitoneal or subcutaneousinjection.

Analoguss of peptides I to VI can be found in HTLV-II See FIG. 1. Suchsequences are:

    GLDLLFWEQGGLCKAIQEQC-X SEQ ID NO: 7                        (VII)

    QNRRGLDLLFWEQGGLCKAIQEQC-X SEQ ID NO: 8                    (VIII)

    NRRGLDLLFWEQGGLC-X SEQ ID NO: 9                            (IX)

    SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS-X SEQ ID NO: 10         (X)

    SSRTILFPSLALPAPPSOPSLWTHCYOPRLQAITTDNCN-X SEQ ID NO: 11    (XI)

    CYQPRLQAITTDNCNNSIILPPFSLAPVPLATRRRRA-X SEQ ID NO: 12      (XII)

(The differences from HTLV-I have been underscored.)

Peptides VII to XII are useful for detecting antibodies to HTLV-II inbody fluids. A review of these sequences show that peptide IX isidentical to peptide III; peptides VII and VIII are identical topeptides I and II except for one amino acid; whereas peptides X, XI andXII contain multiple sites where the amino acids are substitutedaccording to the corresponding HTLV-II amino acids sequence and are,therefore, quite different from that in peptides IV, V and VI.

It has been found that peptide IV and X are specific for HTLV-I andHTLV-II respectively. That is, peptide IV is not s reactive toantibodies to HTLV-II and peptide X is not as reactive to antibodies toHTLV-I. Because of this, peptides IV and X may be used to distinguishbetween HTLV-I and HTLV-II seropositivity.

In addition, according to the present invention, mixtures of peptidesIV-XII may be used to detect the presence of HTLV-I/II in body fluids.Further, a peptide composition useful for the detection of antibodies toHTLV-I/HTLV-II may be used in conjunction with peptide compositionsuseful for the detection of antibodies to HIV-1 and HIV-2, for thesimultaneous detection of infection by both HTLV-I and II and HIV-1 anHIV-2. Peptide compositions useful for the detection of antibodies toHIR-1 and HIV-2 comprise chemically synthesized peptides of thefollowing amino acids, or their analogues, in the prescribed sequenceswherein the sequence for HIV-2 is an analogue of peptide VII and peptideVIII:

HIV-1

    RILAVERYLKDQQLLGIWGCS-X SEQ ID NO: 13                      (XIII)

    IWGCSGKLICTTAVPWNAS-X SEQ ID NO: 14                        (XIV)

    IVRMYSPTSIL-X SEQ ID NO: 15                                (XV)

HIV-2

    DQARLNSWGCAFRQVC SEQ ID NO: 16                             (XVI)

wherein X is --OH or --NH₂, and include analogues, segments, mixturesand polymers thereof, wherein:

    ______________________________________                                        A = Ala = alanine, G = Gly = glycine,                                         R = Arg = arginine,                                                                              I = Ile = isoleucine,                                      D = Asp = aspartic acid,                                                                         F = Phe = phenylalanine,                                   N = Asn = asparginine,                                                                           S = Ser = serine,                                          Q = Gln = Glutamine,                                                                             W = Trp = tryptophan,                                      E = Glu = Glutamic acid,                                                                         Y = Tyr = tyrosine,                                        L = Leu = Leucine, V = Val = valine,                                          K = Lys = Lysine,  C = Cys = cysteine,                                        H = His = histidine                                                                              P = Pro = proline                                          T = Thr = threonine                                                           M = Met = methionine                                                          ______________________________________                                    

The underlined amino acids indicate the residues shared between variousisolates. For HIV-2 peptide XVI, substitutions were made in thecorresponding HIV-2 envelope protein amino acid sequence that would bepredicted from the nucleotide sequence.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows and compares the amino acid sequences of the HTLV-I andHTLV-II envelope proteins.

FIG. 2 shows the amino acid sequences of the chemically synthesizedpeptides described herein.

FIG. 3 is a histogram depicting the immunoreactivities described herein,with sera from ATL patients.

FIG. 4 is a histogram depicting the immunoreactivities of the peptidesdescribed herein with sera from patients with HIV infection, patientswith ATL, and random blood donors.

FIG. 5 is a histogram depicting the simultaneous detection of antibodiesto HTLV-I and HIV (1 and 2) by an enzyme immunoassay employing a mixtureof seven chemically synthesized peptides described herein.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the present invention, six peptides have beenchemically synthesized for the detection of antibodies to HTLV-I orHTLV-II in body fluids and the diagnosis of ATL, and for the vaccinationof healthy mammals by stimulating the production of antibodies to HTLV-Ior HTLV-II in healthy mammals. These peptides are arranged in thefollowing sequences:

    GLDLLFWEQGGLCKALQEQC-X SEQ ID NO: 1                        (I)

    QNRRGLDLLFQEQGGLCKALQEQC-X SEQ ID NO: 2                    (II)

    NRRGLDLLFWEQGGLC-X SEQ ID NO: 3                            (III)

    APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS-X SEQ ID NO: 4          (IV)

    SSTPLLYPSLALPAPHLTLPFNWTHCFDPQIQAIVSSPCH-X SEQ ID NO: 5    (V)

    CFDPQIQAIVSSPCHNSLILPPFSLSPVPTLGSRSRRA-X SEQ ID NO: 6      (VI)

    SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS-X SEQ ID NO: 10         (X)

wherein X is --OH or --NH₂.

These peptides may also comprise conjugates, i.e., they may be coupledto carrier proteins such as bovine serum albumin (BSA) or human serumalbumin (HSA). Furthermore, these peptides may comprise polymers, i.e.,they may be synthesized on a polymeric resin, such as a branchingoctameric lysine resin. It is expected that as long as the peptideimmunoreactivities recognizable by the antibodies to HTLV-I/HTLV-II arepreserved, analogues of the synthetic peptide may also comprisesubstitutions, insertions and/or deletions of the recited amino acids ofthe above sequence.

In addition, to accommodate strain-to-strain variations among differentisolates, adjustments for conservative substitutions and selection amongthe alternatives where non-conservative substitutions are involved, maybe made in the prescribed sequences. For example, peptides X to XIIfound in the HTLV-II strain may also be used.

The amino acid sequences of the polypeptides useful as test reagents forthe detection of antibodies to HTLV-I or HTLV-II in body fluids anddiagnosis of ATL are selected to correspond to a partial segment of theamino acid sequence of the HTLV-I virus designated as gp21, and to apartial segment of the amino acid sequence of the HTLV virus designatedas gp46, both parts of gp61, which defines the envelope protein of theHTLV-I or HTLV-II virus.

The peptides useful as solid phase immunoadsorbents for the detection ofantibodies HTLV-I were synthesized by the "classical" Merrifield methodof solid phase peptide synthesis using side chain protected t-Boc-aminoacids to correspond to the following amino acid sequences:

    APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS-X SEQ ID NO: 4          (IV)

    SSTPLLYPSLALPAPHLTLPFNWTHCFDPQIQAIVSSPCH-X SEQ ID NO: 5    (V)

    CFDPQIQAIVSSPCHNSLILPPFSLSPVPTLGSRSRRA-X SEQ ID NO: 6      (VI)

    SPPLVHDSDLEHVLTPSTSWTTILKFIQLTLQS-X SEQ ID NO: 10          (X)

wherein X is --OH or --NH₂.

Other analoguss of these peptides can be prepared by varying the aminoacid sequences either by adding, subtracting, substituting, or deletingdesired t-Boc-amino acid(s).

For example, analogue peptides VII to XII having following sequences canalso be prepared.

    GLDLLFWEQGGLCKAIQEQC-X SEQ ID NO: 7                        (VII)

    QNRRGLDLLFWEQGGLCKAIQEQC-X SEQ ID NO: 8                    (VIII)

    NRRGLDLLFWEQGGLC-X SEQ ID NO: 9                            (IX)

    SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS-X SEQ ID NO: 10         (X)

    SSRTILFPSLALPAPPSQPSLWTHCYQPRLQAITTDNCN-X SEQ ID NO: 11    (XI)

    CYQPRLQAITTDNCNNSIILPPFSLAPVPLATRRRRA-X SEQ ID NO: 12      (XII)

Following completion of assembly of the desired blocked peptide on theresin, the peptide-resin is treated with anhydrous hydrofluoric acid tocleave the peptide from the resin. Functional groups of amino acidswhich are blocked during synthesis by benzyl-derived blocking groups arealso cleaved from the peptide simultaneously. The free peptide is thenanalyzed and purified by high performance liquid chromatography (HPLC)and characterized biochemically by amino acid analysis.

The peptides synthesized according to the above described procedure arehighly reactive to antibodies to HTLV-I and/or HTLV-II and can be usedas a highly sensitive and specific immunoadsorbent for the detection ofthe antibodies against HTLV-I and/or HTLV-II.

FIG. 3 show the data obtained with sera from ATL patients using an ELISAmethod wherein the well plates are coated with peptides IV, V and VI at1.0 ug of each. Table I shows the data obtained with sera from ATLpatients using an ELISA method wherein the well plates are coated with amixture of peptides II, IV, v and VI, in a weight ratio of 1:0.25:1:1(II;IV;V;VI). Table II shows the data obtained with sera from ATLpatients utilizing an agglutination method wherein the red blood cells(RBC) are coated with a peptide VI-BSA conjugate. Tables III and IV showthe unique and specific immuno reactivities associated with peptide IVand peptide X and their usefulness in differentiating between subjectswith HTLV-I or HTLV-II infections.

Based on the high degree of sensitivity and specificity of the peptidecompositions according to the present invention in the immunoreaction toantibodies to HTLV-I and/or HTLV-II, it is believed that these peptidecompositions may also be useful as a vaccine for ATL, and/or HTLV-IIinfection, and as immunogens for the development of both monoclonal andpolyclonal antibodies to HTLV-I and/or HTLV-II in mammals, includinghumans. The peptide compositions when coupled to a protein orsynthesized on a polymer carrier resin (e.g., an octameric lysine resin)or when polymerized to homo or hetero dimers or higher oligomers bycystsine oxidation, induced disulfide cross linking, or when polymerizedto homo or hetero dimers or higher oligomers by use of homo or heretofunctional multivalent cross linking reagents, can be introduced tonormal subjects to stimulate production of antibodies to HTLV-I and/orHTLV-II, and provide protection against infection by HTLV-I and/orHTLV-II in healthy mammals. Since the peptide composition according tothe present invention is not derived biochemically from the virus, thereis no danger of exposing the normal subjects who are to be vaccinated tothe disease.

The advantages of using the peptides according to the present inventionare many.

The peptides are chemically synthesized. This means that there is noinvolvement with the HTLV-I or HTLV-II virus at any time during theprocess of making the test reagent or the vaccine. During thepreparation of the vaccine or the vaccination process, productionworkers or individuals in the health professions do not risk exposure tothe HTLV-I or HTLV-II virus. Further, up to the final step of the testto detect antibodies to HTLV-I or HTLV-II, where the test reagent isexposed to samples of sera or body fluid, there is no risk of exposureof the laboratory worker to the HTLV-I or HTLV-II virus.

Another problem which is avoided by the process of the present inventionis the possibility of false positive results caused by the presence ofantigenic materials from host cells purified with the HTLV-I or HTLV-IIviral lysate preparation or E-Coli derived proteins co-purified withexpressed viral fragments. Certain normal individuals have antibodies toE. Coli or human leukocyte antigens, e.g. HLA, which are cross reactivewith the antigenic materials from host cells. Sera samples from thesenormal individuals may show a positive response in the ELISA or IRMAtests.

Further, with appropriate amino acid analogue substitutions, it isexpected that various peptide analogues based on the prescribed aminoacid sequence can be synthesized with properties giving rise to lowerbackground readings or better adsorption capacity to solid phases usefulfor HTLV-I or HTLV-II antibodies screening assays.

Moreover, because the peptide compositions of the present invention aresynthetically prepared, the quality can be controlled and as a result,reproducibility of the test results can be assured. Also, since verysmall amounts of peptides are required for each test procedure, andbecause the expense of preparing the peptides is relatively low, thecost of screening body fluids for antibodies to HTLV-I or HTLV-II, anddiagnosis of ATL and/or HTLV-II infection and the preparation of avaccine is relatively low.

The peptides prepared in accordance with the present invention can beused to detect HTLV-I and/or HTLV-II infection and diagnosis ATL byusing it as the test reagent in an enzyme-linked immunoadsorbent assay(ELISA), an enzyme immunodot assay, an agglutination assay, aradioimmunoradiometric assay (IRMA), or other well-known immunoassays.The preferred method is ELISA. The ELISA technique is exemplified inExamples 1 and 2, the IRMA technique is exemplified in Example 5, andthe agglutination assay in Examples 3 and 6.

It is to be noted that in the following methods, 0.25% by weight ofglutaraldehyde may be added in the coating buffer to facilitate betterpeptide binding onto the blades or beads. Further, horseradishperoxidase conjugated mouse monoclonal anti-human IgG antibody may beused in place of horseradish peroxidase conjugated goat anti-human IgGas the second antibody tracer.

The gelatin used in these processes can include calf skin gelatin, pigskin gelatin, fish gelatin or any known available gelatin proteins or bereplaced with albumin proteins.

In Example 10, it is shown that peptide IV is preferentially reactive toantibodies to HTLV-I and not reactive to HTLV-II and thus can be used todistinguish HTLV-I infection from HTLV-II infection.

Similarly, in Example 11, it is shown that peptide X, which is ananalogue peptide derived from the amino acid sequence of HTLV-II, avariant of HTLV-I, is only reactive to antibodies to HTLV-II and can beused to specifically detect HTLV-II infection.

EXAMPLE I Detection of Antibodies to HTLV-I/HTLV-II by an Enzyme-LinkedImmunoadsorbent Assay

Wells of 96-well plates were each coated at 4° C. overnight (or 3 hoursat room temperature), with each of the three peptides IV, V, VI preparedas described at 1.0 ug each per well per peptide in 100 ul 10 mM NaHCO₃buffer, pH 9.5. The wells were washed three times with phosphatebuffered saline (PBS) and then incubated with 250 ul of 3% by weight ofgelatin in PBS at 37° C. for I hour to block non-specific proteinbinding sites, followed by three more washes with PBS containing 0.05%by volume of Tween 20. The test sera (blood taken from a patient ornormal individual) were diluted with PBS containing 20% by volume normalgoat serum, 1% by weight gelatin and 0.05% by volume Tween 20 atdilutions of 1:20 volume to volume, respectively. 200 ul of the dilutedsera were added of each well and allowed to react for 1 hours at 37° C.The wells were then washed three times with 0.05% by volume Tween 20 inPBS in order to remove unbound Horseradish peroxidase conjugated goatanti-human IgG was used as a second antibody tracer to bind with theHTLV-I antibody-antigen complex formed in positive wells. 100 ul ofperoxidase labeled goat anti-human IgG at a dilution of 1:3000 in 1% byvolume normal goat serum, 0.05% by volume Tween 20 in PBS was added toeach well and incubated at 37° C. for another 15 minutes.

The wells were washed five times with 0.05% by volume Tween 20 in PBS toremove unbound antibody and reacted with 100 ul of the substrate mixturecontaining 0.04% by weight orthophenylenediamine (OPD) and 0.012% byvolume hydrogen peroxide in sodium citrate buffer, pH 5.0. Thissubstrate mixture was used to detect the peroxidase label by forming acolored product. Reactions were stopped by the addition of 100 ul of1.0M H₂ SO₄ and the absorbance measured using an ELISA reader at 492 nm(i.e. A₄₉₂). Assays were performed in duplicate with one dilution (1:20)of serum samples from normal individuals or from patients with diseasesunrelated to HTLV-I infection used as negative controls. Absorbancereadings greater than the cutoff value of A₄₉₂ =0.12, (about 3× the meanA₄₉₂ value of normal serum control), were taken as positive. The resultsare shown in FIG. 3.

EXAMPLE 2 Detection of Antibodies to HTLV by an Enzyme-LinkedImmunoadsorbent Assay

Wells of 96-well plates were coated at 4° C. overnight (or for 3 hoursat room temperature or for 1 hour at 37° C.), with a mixture of fourpeptides prepared as described in a ratio by weight ofII:IV:V:VI=1:0.25:1:1 at 3.25 ug per well of the mixture in 100 ul 10 mMNaHCO₃ buffer, pH 9.5. The wells were washed three times with phosphatebuffered saline (PBS) and then incubated with 250 ul of 3% by weight ofgelatin in PBS at 37° C. for 1 hour to block non-specific proteinbinding sites, followed by three more washes with PBS containing 0.05%by volume of Tween 20. The test sera (blood taken from human patients ornormal individuals) were diluted with PBS containing 20% by volumenormal goat serum, 1% by weight gelatin and 0.05% by volume Tween 20 atdilutions of 1:20, volume to volume, respectively. 200 ul of the dilutedsera were added to each well and allowed to react for 1 hour at 37° C.The wells were then washed three times with 0.05% by volume Tween 20 inPBS in order to remove unbound antibodies. Horseradish peroxidaseconjugated goat anti-human IgG was used as a second antibody tracer tobind with the HTLV antibody-antigen complex formed in positive wells.100 ul of peroxidase labeled goat anti-human IgG at a dilution of 1:3000in 1% by volume normal goat serum, 0.05% by volume Tween 20 in PBS wasadded to each well and incubated at 37° C. for another 15 minutes.

The wells were washed five times with 0.05% by volume Tween 20 in PBS toremove unbound antibody and reacted with 100 ul of the substrate mixturecontaining 0.04% by weight orthophenylenediamine (OPD) and 0.012% byvolume hydrogen peroxide in sodium citrate buffer, pH 5.0. Thissubstrate mixture was used to detect the peroxidase label by forming acolored product. Reactions were stopped by the addition of 100 ul of1.0M H₂ SO₄ and the absorbance measured using an ELISA reader at 492 nm(i.e. A₄₉₂). Assays were performed in duplicate with one dilution (1:20)of serum samples from normal individuals or from patients with diseasesunrelated to HTLV infection used as negative controls. Absorbancereadings greater than the cutoff value of A₄₉₂ =A₄₉₂ value for normalcontrol+0.1 (A₄₉₂ value for a reactive control), were taken as positive.The results are shown in Table I and FIG. 4.

                  TABLE I                                                         ______________________________________                                        Detection of Antibodies to HTLV                                               by ELISA* Using a Mixture of Four                                             Peptides as Solid Phase Immunoadsorbent                                                            No. Positive/                                                                           Percent                                        Subject              No. Tested*                                                                             Positive                                       ______________________________________                                        1.    Patients (Lot 5) with ATL                                                                        94/94     100                                              (HTLV Western Blot Positive)                                            2.    Patients (Lot 5) with ATL                                                                        0/6       0                                                (HTLV Western Blot Negative)                                            3.    Patients with AIDS/ARC or                                                                         10/161   6                                                known to be infected with HIV                                           4.    Normal Subjects     0/200    0                                          ______________________________________                                         *Assay was performed using sera at 1:20 (v/v) dilution with buffer.           Note:                                                                         Sera from patients with ATL were kindly provided by the Japanese Red          Cross, sera from patients with AIDS ARC, Primary Immunodeficiency,            Leukemia/Lymphomas were kindly provided by Dr. S. Gupta at the University     of California at Irvine, Dr. D. M. Knowles at Columbia University, and Dr     F. D. Siegal at the Long Island Jewish Hospital.                         

The results in Table show that the ELISA test procedure according to thepresent invention with sera samples is very accurate and highlyspecific. No immunoreactivity was found in sera from normal subjects.

It is to be noted that in screening tests to exclude virus contaminatedblood from blood banks, the criteria for defining positive reactions maybe made more stringent if desired.

EXAMPLE 3 Detection of Antibodies to HTLV by an Agglutination Assay

The presently claimed HTLV peptides, synthesized according to theMerrifield solid phase method, were conjugated to bovine serum albumin(BSA) which had been derivatized withm-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS), essentially asdescribed by Fu-Tong Liu et al., in Biochemistry 18:690-697 (1979). To0.32 ml. of a BSA solution (100 mg/ml in 0.01M phosphate buffer, pH 7.0)at room temperature was added 0.013 ml of an MBS solution (0.025 mg/mlin dimethylformamide). The amount of MBS added to the BSA solution canbe varied according to the optimal molar ratio of BSA to MBS determinedfor a specific conjugate studied. The mixture was stirred at roomtemperature for 1 hour, after which it was centrifuged to remove anyprecipitated albumin. The clarified mixture was then subjected to gelfiltration on Sephadex G-25 and the protein-containing fractions, asdetected by their absorbance at 280 nm, were pooled and stored frozen at-70° C. until needed.

The peptides were dissolved in H₂ O at 10 mg/ml. A predetermined amountof each peptide solution was added dropwise to the previously activatedBSA-MBS solution and stirred at room temperature for 3 hours. The finalpeptide-BSA conjugates were separated from other free peptides by gelfiltration or extensive dialysis. The ratio of peptide of BSA wasdetermined by SDS-PAGE according to conventional methods.

In one example, conjugated peptide VI-BSA was then adsorbed to doublealdehyde fixed human o erythrocytes at pH 4.0. The peptide-conjugatecoated erythrocytes were then washed with PBS and incubated with 5%normal human serum-PBS solution. These processed cells were then used inan agglutination assay for the detection of HTLV antibodies in bothserum and plasma specimens.

A total of 100 sera from patients with adult T cell leukemia were testedfor antibodies to HTLV by (1) an enzyme immunoassay (EIA) employingHTLV-I vital lysate as the solid phase DuPont's HTLV-I ELISA!; (2) theWestern Blot (WB) analysis; (3) the above-described HTLV agglutinationassay employing peptide VI-BSA conjugate as the solid phase.

The results are shown in Table II.

                  TABLE II                                                        ______________________________________                                        Results                                                                       WB        No. Tested                                                                              EIA      HTLV Agglutination Assay                         ______________________________________                                        +         77        +        77 positive +                                    intdeterm.                                                                               2        +         2 negative*                                     -         21        -        21 negative                                      ______________________________________                                         *The two specimens that tested negative with the HTLV agglutination assay     were found to have antibodies only to the p19 core protein of HTLV.      

EXAMPLE 4 Simultaneous Detection of Antibodies to HTLV and HIV (1 and 2)by an Enzyme Immunoassay Employing a Mixture of Seven ChemicallySynthesized Peptides

A solution containing seven of the chemically synthesized peptides ofthe present invention was used to coat the wells of 96 well plates,according to the procedure of Example I. Three of the peptides werederived from the HTLV-I peptide family II, IV and VI!; three, from theHIV-1 peptide family XIII, XIV and XV!; and one, from the HIV-2 peptidefamily XVI!. The peptides II:IV::VI:XIII:XIV:XV:XVI were present at aratio of 2:0.2:2:10:1:1:5 for a total concentration of 21.2 ug/ml. Atotal of 771 specimens from donors known to be HIV-1 positive (155specimens); HIV-2 positive (10 specimens); HTLV positive by Wester Blot(92) specimens); HTLV negative by Western Blot (4 specimens); patientswith autoimmune diseases (AI, 36 specimens); and, from random blooddonors (RBD, 474 specimens), were tested on the peptide-coated platesfor their respective retroviral immunoreactivies.

Performance of this synthetic peptide-based retroviralcombo EIA (HTLVand HIV-1 and 2) with these specimens is illustrated in FIG. 5. Theresults clearly indicate the usefulness of these HTLV peptides inconjunction with the HIV peptides for the detection of retroviralinfections.

EXAMPLE 5 Detection of Antibodies to HTLV by an Immunoradiometric Assay(IRMA)

Wells of 96-well flexible-polyvinylchloride (PVC) plates are coated at4° C. overnight (or 3 hours at room temperature) with a mixture (1:1:1)of these three peptides, prepared as described, at 1.5 ug per well in100 ul 10 mM NaHCO₃ suffer, pH 9.5. The wells are washed three timeswith phosphate buffered saline (PBS) and then incubated with 250 ul of3% by weight gelatin in PBS at 37° C. for 1 hour to block non-specificprotein binding sites, followed by three more washes with PBS containing0.05% by volume Tween 20. The test sera (blood taken from a humanpatient or normal individual) are diluted with PBS containing 20% byvolume normal goat serum, 1% by weight gelatin 9 and 0.05% by volumeTween 20 at dilutions of 1:20 and 1:200 (volume to volume) respectively.200 ul of the diluted sera are added to each cell and allowed to reactfor 1 hour at 37° C. The wells are then washed three times with 0.05% byvolume Tween 20 in PBS in order to remove unbound antibodies. I-125labeled affinity purified goat anti-human IgG is used as a secondantibody purified goat anti-human IgG of 50,000-200,000 cpm in 1% byvolume normal goat serum, 0.05% by volume Tween 20 in PBS is added toeach well and incubated at 37° C. for another hour.

The wells was washed five times with 0.05% by volume Tween 20 in PBS toremove unbound second antibody and dried. The wells are cut and countedby a gamma-scintillation counter. Assays are performed in duplicate witha 1:20 dilution volume to volume. Normal sera sample is negativecontrols are also tested simultaneously. Cpm readings greater than theaverage readings of normal sera samples+4SD (standard deviation) aretaken as positive.

EXAMPLE 6 Detection Of Antibodies To HTLV By An Agglutination AssayUtilizing As The Solid Phase Immunoadsorbent Gelatin Particles,Erythrocytes Of Different Animal Species, Or Latex Beads Coated With AMixture Of Peptides

One ml thoroughly washed erythrocytes, gelatin particles, or polystyrenelatex beads are coated with the peptide mixture at concentration in therange of 5 ug/ml to 1 mg/ml. The peptide mixture coated cells, particlesor beads are then incubated with serially diluted serum samples in thewells of a 96-well U-shaped microplate or on a slide. After being leftat room temperature for about an hour, the settled agglutinationpatterns on the bottom of the wells or on the slide are read, and thelargest dilution showing a positive reaction is recorded.

This is a one-step assay which could be used for both qualitative andquantitative analysis for the presence of antibodies to HTLV inspecimens including sera or biofluids.

EXAMPLE 7

A third test kit for detecting HTLV antibodies using the agglutinationassay comprises a compartmented enclosure containing multiple microwellplates and other accessory materials for an agglutination assayincluding (1) a bottle of peptide mixture coated erythrocytes, gelatinparticles or latex polystyrene beads; (2) normal human serum (as anegative control); and, (3) NP40 treated and heat inactivated, HTLV-Iseropositive serum (as a positive control), and (4) specimen diluent.The procedure described in Example 3 is to be followed.

EXAMPLE 8

A diagnostic test kit for the detection of HTLV antibodies can beconstructed. The test kit comprises a compartmented enclosure containingmultiple 96-well plates coated prior to use with the peptide(s) orpeptide mixture(s) of the present invention in 100 ul pH 9.5 10 mMNaHCO₃ buffer. The kit further comprises materials for enzyme detectionin separate sealed containers consisting of: 1) normal human serum (as anegative control); 2) NP40 treated and heat inactivated, HTLV-Iseropositive serum (as a positive control); 3) specimen diluent; 4)peroxidase labeled-goat antihuman IgG; and 5) a color change indicatorconsisting of, for example, orthophenylenediamine (OPD) and hydrogenperoxide in phosphate citrate buffer. The procedure described in ExampleI is to be followed.

In this test, 96-well plates, precoated with a peptide or peptidemixture of the present invention, can be replaced by polystyrene beads,or multiple mini-columns filled with controlled pore size glass beads,or nitrocellulose paper strips precoated with the peptides of thepresent invention for use as the solid phase immunoabsorbent.

EXAMPLE 9

A second test kit for detecting antibodies using the immunoradiometricassay (IRMA) comprises a compartmented enclosure containing multiple96-well bendable polyvinychloride (PVC) plates precoated with thepeptide(s) or peptide mixture(s) according to the present invention in100 ul of pH 9.5 10 mM NaHCO₃ buffer and materials for radioimmunoassayincluding: 1) normal human serum (as a negative control); 2) NP40treated and heat inactivated, HTLV-1 seropositive serum (as a positivecontrol); 3) specimen diluent; and, 4) I-125 labeled goated anti humanIgG. The procedure described in Example 5 is to be followed.

In this test kit, 96-well PVC plates precoated with the peptides of thepresent invention can be replaced by polystyrene beads precoated withthe peptide of the present invention for use as the solid phaseimmunoadsorbent.

EXAMPLE 10 Specific Detection of Antibodies to HTLV-I and not HTLV-II ByAn Enzyme Immunoassay Employing A Synthesized Peptide

A solution containing the synthesized HTLV-I peptide (IV) of the presentinvention at 5ug/ml having the sequence corresponding to HTLV-I,APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS, SEQ ID NO: 4 was used to coat thewells of 96 well plates, according to the procedure of Example 1. Atotal of 120 specimens from blood donors or individuals known to berepeat reactive on an HTLV lysate based test were tested on thepeptide-coated plates for their immunoreactivity. Of the 120 samples, 73had also been tested by polymerase chain reaction with HTLV-I or HTLV-IIspecific DNA probes (PCR). Of these, 43 were positive for HTLV-I by PCRand 30 were positive for HTLV-II by PCR. Supplemental testings, such asWestern Blot and radioimmuno-precipitation assay (RIPA), were alsoperformed on all 120 samples. For those samples with no PCR resultsavailable, the WB and RIPA results were considered as probably HTLV-1 orHTLV-II positive. The 120 samples thus comprised the followingcategories: HTLV-I positive by PCR (43 specimens); probably HTLV-Ipositive by Western Blot and RIPA (12 specimens); HTLV-II positive byPCR (30 specimens); probably HTLV-II positive by Western Blot and RIPA(26 specimens); and repeat reactive for HTLV by vital lysate ELISA, butnegative by Western Blot and negative by RIPA (RR (WB NEG), 9specimens).

Performance of this synthetic peptide-based EIA (HTLV-I specific) ispresented in Table III. The results in Table III show that the method ishighly sensitive and specific for HTLV-I and that it can be used todistinguish HTLV-II from HTLV-I infection. The whole virus lysate EIA,on the other hand, does not distinguish between the two vital infectionssince it gave positive results for all 120 sample.

                  TABLE III                                                       ______________________________________                                        TESTED BY PEPTIDE IV                                                          Subject            No. Positive/                                                                           Percent                                          (confirmed by)     No. Tested                                                                              Positive                                         ______________________________________                                        1.     HTLV-I (PCR)    41/43     95.3                                         2.     HTLV-I (WB/RIPA)                                                                              12/12     100                                          3.     HTLV-II (PCR)    4/30     13.3                                         4.     HTLV-II (WB/RIPA)                                                                              1/26     3.8                                          5.     RR (WB NEG)     0/9       0                                            ______________________________________                                    

Sera from blood donors and individuals known to be HTLV-I or HTLV-IIpositive, confirmed either by PCR, RIPA or WB, were kindly provided bySerologicals, Inc. and by Dr. Chang Fang of the American Red Cross(ARC).

EXAMPLE 11 Specific Detection of Antibodies to HTLV-II and not HTLV-I ByAn Enzyme Immunoassay Employing A Synthesized Peptide

A solution containing a synthetic peptide analogue of the HTLV-I peptideIV of the present invention, designated as HTLV-II peptide X, having thesequence corresponding to HTLV-II in FIG. 2, i.e., with an amino acidsequence of SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS , SEQ ID NO: 10 was usedat a concentration of 5 ug/ml to coat the wells of 96 well plates,according to the procedure of Example 1. The same 120 specimens as inExample 10 were tested.

Performance of this synthetic peptide-based EIA (HTLV-II specific) ispresented in Table IV. The results in Table IV show that the method ishighly sensitive and specific for HTLV-II and that it can be used todistinguish antibodies against HTLV-II from antibodies against HTLV-I.The whole virus lysate EIA, on the other hand, does not distinguishbetween the two viral infection since it gave positive results for all120 samples.

                  TABLE IV                                                        ______________________________________                                        TESTED BY PEPTIDE X                                                           Subject            No. Positive/                                                                           Percent                                          (confirmed by)     No. Tested                                                                              Positive                                         ______________________________________                                        1.     HTLV-II (PCR)   28/30     93.3                                         2.     HTLV-II (WB/RIPA)                                                                             24/26     92.3                                         3.     HTLV-I (PCR)     0/43     0                                            4.     HTLV-I (WB/RIPA)                                                                               0/12     0                                            5.     RR (WB NEG)     0/9       0                                            ______________________________________                                    

EXAMPLE 12

Two peptides were synthesized to have amino acid sequences whichcorrespond to segments of APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS SEQ ID NO:4 (IV) AND SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS (V). The sequence of thepeptide segments are as follows:

    APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS SEQ ID NO: 4            (IV)

    PHSNLDHILEPSIPWKSKLLTLVQLTLQS SEQ ID NO: 17                (IVA)

    SPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS SEQ ID NO: 10           (X)(V)

    HDSDLEHVLTPSTSWTTKILKFIQLTLQS SEQ ID NO: 18                (XA)(VA)

The synthesized peptides were used in an ELISA against sera which havebeen found to be positive for antibodies to HTLV-I and HTLV-II. Theprocedure described in Example 1 of the above identified patentapplication was followed.

The results in absorbance at 492 nm (A₄₉₂ nm) obtained are tabulatedbelow.

                  TABLE V                                                         ______________________________________                                                  IV   IVA        X       XA                                          ______________________________________                                        BG*         0.004  -0.001     -0.008                                                                              0.002                                     NRC*        0.017  0.010      0.069 0.046                                     HTLV(+), sera                                                                 9-301       2.239  1.682      0.281 0.292                                     9-302       0.738  0.545      0.065 0.091                                     9-307       4.030  3.462      0.084 0.159                                     9-310       0.145  0.053      0.187 0.095                                     9-312       2.499  3.329      0.051 0.040                                     9-321       0.391  0.521      0.143 0.165                                     9-326       2.641  1.215      0.090 0.096                                     9-329       4.030  3.365      0.077 0.074                                     9-317       0.017  0.069      3.862 0.211                                     9-323       0.025  0.287      0.335 0.100                                     9-350       0.010  0.517      2.713 0.013                                     9-352       0.012  0.168      0.993 0.278                                     9-357       0.022  0.683      2.699 0.187                                     9-359       0.037  0.064      1.187 0.259                                     9-362       0.057  0.202      0.828 0.101                                     9-364       0.046  0.177      0.539 0.212                                     ______________________________________                                         *BG = blank                                                                   **NRC = NonReactive Control                                              

The results show that segments of peptides (IV) and (V) areimmunoreactive to HTLV-I and/or HTLV-II antibodies. The A₄₉₂ nm readings(underlined) show that Peptides IrA and VA are more immunoreactive thanPeptides IV and V respectively in some instances.

EXAMPLE 13

A segment of peptide (IV) having the following amino acid sequence wassynthesized:

    APPLLPHSNLDHILEPSIPWK                                      (IVB)

This segment peptide (IVB) and peptide (IV) were also tested inaccordance with Example 1 of the above identified patent application inan ELISA assay using HTLV-I positive sera and the results compared inTable II. The results showed that peptide (IVB) is immunoreactive toantibodies to HTLV.

                  TABLE VI                                                        ______________________________________                                                      Peptide IV                                                                           Peptide IVB                                                            A.sub.492nm                                                                          A.sub.492nm                                              ______________________________________                                        BG              0.043    0.040                                                NRC             0.026    0.031                                                HTLV(+), sera                                                                 9-301           1.487    2.323                                                9-302           0.379    0.418                                                9-307           3.065    3.309                                                9-310           0.461    0.406                                                9-312           1.430    1.167                                                9-321           0.268    0.371                                                9-326           1.701    1.645                                                9-329           3.392    3.092                                                9-330           0.004    0.012                                                9-334           0.039    0.040                                                9-339           0.321    0.352                                                9-341           0.321    0.460                                                9-342           0.430    0.552                                                9-345           0.309    0.394                                                9-361           1.251    2.139                                                9-363           0.023    0.025                                                9-374           3.245    3.494                                                9-367           2.100    2.473                                                ______________________________________                                    

The A₄₉₂ nm readings (underlined) showed that Peptide IVB has higherimmunoreactivity than the corresponding Peptide IV in some instances.

EXAMPLE 14

Octameric peptides (IV) and (V) on a branching lysine core polymer weresynthesized and tested in accordance with Example 1 of the aboveidentified patent application in an ELISA against HTLV-I and HTLV-IIpositive sera, respectively.

The results obtained were:

                  TABLE VII                                                       ______________________________________                                        Peptide     Octameric           Peptide                                                                             Octameric                               IV          IV                  X     X                                       ______________________________________                                        BL      0.042   0.039     BL      0.055 0.046                                 NRC     0.027   0.082     NRC     0.035 0.096                                 HTLV-I(+)                 HTLV-I(+)                                           Sera code                 Sera code                                           9-301   2.329   3.451     9-317   3.862 3.620                                 9-302   0.738   2.681     9-323   0.335 0.561                                 9-307   4.000   3.113     9-350   2.713 2.455                                 9-310   0.145   1.111     9-352   0.993 1.058                                 9-312   2.499   3.375     9-357   2.699 3.170                                 9-321   0.391   1.498     9-359   1.187 1.532                                 9-326   2.993   3.388     9-362   0.828 0.574                                 9-329   3.140   3.355     9-364   0.539 0.791                                 9-339   0.624   2.467                                                         9-341   1.351   3.495                                                         9-342   1.272   3.181                                                         9-345   0.591   0.941                                                         9-361   1.050   3.217                                                         9-363   0.043   0.038                                                         9-374   3.346   3.212                                                         9-397   3.315   2.657                                                         Relative                                                                              100%    143.7%            100%  105%                                  Immuno-                                                                       reactivity                                                                    ______________________________________                                    

The A492 nm readings (underlined) indicate higher immunoreactivity ofthe octameric peptides than their corresponding parent peptides IV andX. The results also show that polymers of Peptides IV and X areimmunoreactive.

EXAMPLE 15 SYNTHESIS OF OCTAMERIC HTLV PEPTIDE ANTIGENS AS KEYCOMPONENTS OF IMMUNOGENS/VACCINES

The use of a limited sequential propagation of a trifunctional aminoacid (or similar analogues) to form a core that serves as a lowmolecular weight matrix is the basic underlying principle for theformation of a radially branching multimerit peptide antigen system. Thetrifunctional amino acid, Boc-Lys(Boc), or di-(Boc)-Lys is most suitablesince both N-a and N-e amino acid groups are available as reactive ends.

An octameric heptalysyl core resin was prepared by coupling di-t-Boc Lysonto an extra low loading 0.14 mmole/g MBHA (4-methyl benzhydrylamine)resin on a Biosearch 9500 instrument. During each of the two couplingcycles, di-(Boc)-Lys was used for^(i) single coupling followed by twocapping reactions (with 0.3M acetylimidazole in DMF dimethylformamide).

After two additional di-(Boc)-Lys couplings onto the first di-(NH₂)Lys-resin, the substitution level of synthetic octameric resin wasdetermined by ninhydrin test and found to be in the range as calculatedbased on a theoretical coupling yield. The resin was used thereafter forthe synthesis of octameric peptide immunogens.

Acid-labile tert-butyloxycarbonyl (y-Boc) was used for the protection ofN-a amino acid. The following functional side-chain protecting groupswere used: O-benzyl for Thr, Set, Glu and Tyr; N-tosyl for Arg; BOM(i.e. Boc-N^(im) -Benzyloxymethyl-) for His; N-dichlorobenzyl-oxycarbonyl for Lys; S-4-methylbenzyl- for Cys; O-cyclohexyl for Asp andCHO for Trp. Successive amino acids were added for the synthesis ofoctameric HTLV-1 envelope peptide according to the sequenceAPPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS SEQ ID NO: 4 (IV) and octamericHTLV-II envelope peptide according to the sequence ofSPPLVHDSDLEHVLTDSTSWITKILKFIQLTLQS SEQ ID NO: 10 (X). The resultantoctameric peptidyl resin for each of the synthesis was cleaved byanhydrous HF. The released octameric antigen was extracted by aceticacid, 8 after two cycles of either washings of the cleaved peptidylresin, and lyophilized to dryness so as to be ready for use as animmunogen.

These HTLV-I/II octameric peptides were injected individually and as amixture into healthy, naive animals (guinea pigs and rabbits) bothintramuscularly and subcutaneously at a dosage of 100 ug peptide incomplete/incomplete Freund's adjuvant. After the initial immunization,these animals were boosted at the same dose at 3, 6 and 32 weeks. Theanimals were bled monthly and the collected immune sera were tested fortheir anti-HTLV-I/II envelope peptide immunoreactivity by enzymeimmunoassays as shown in Table VIII. Six months after the last boost,the immunized rabbits were challenged by experimental inoculation withHTLV-I or HTLV-II infected cells to evaluate the efficacy in using amixture of these octameric envelope peptides as a vaccine for theprevention of HTLV infection.

                  TABLE VIII                                                      ______________________________________                                                      Coating Antigen (5 ug/mL @                                                    0.1 mL per well) O.D. 492 nm EIA                                                                (Monomeric                                                           HTLV-I   IV)                                           a HTLV-I (Octa IV)                                                                            1:102  1:103    1:10.sup.4                                                                            1:10.sup.5                            ______________________________________                                        Prebleed Control                                                                        (0 wpi)   0.013                                                     G.p.A     3 wpi     3.563  3.626  2.074   0.171                               G.p.A     12 wpi    3.396  3.638  2.976   0.580                               G.p.A     21 wpi    3.571  3.607  1.743   N.D.                                ______________________________________                                                                        (Monomeric                                                           HTLV-I   X)                                            a HTLV-II (Octa X)                                                                            1:102  1:103    1:10.sup.4                                                                            1:10.sup.5                            ______________________________________                                        Prebleed Control                                                                        (0 wpi)   0.000                                                     G.p.A     9 wpi     3.543  3.699  3.311   0.583                               G.p.A     12 wpi    3.378  3.173  2.476   0.376                               ______________________________________                                    

Representative data points from immunized guinea pigs A and B bled overa three to five months period as shown in Table VIII indicated that hightiters of anti-HTLV-I envelop peptide (IV) or anti-HTLV-II envelopepeptide (X) reactivity were obtained from as early as three weeks afterimmunizations and the titers remained high throughout the five monthsperiod, evidence of strong immunogenicity of the octameric HTLVimmunogens (IV and X), thus their efficacious nature as key componentsin a vaccine.

It is to be understood that the above examples are illustrative of thepresent invention and are not meant to limit the scope thereof.

    __________________________________________________________________________    SEQUENCE LISTING                                                              (1) GENERAL INFORMATION:                                                      (iii) NUMBER OF SEQUENCES: 19                                                 (2) INFORMATION FOR SEQ ID NO:1:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 20                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:                                       GlyLeuAspLeuLeuPheTrpGluGlnGlyGlyLeuCysLysAla                                 151015                                                                        LeuGlnGluGlnCys                                                               20                                                                            (2) INFORMATION FOR SEQ ID NO:2:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 24                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:                                       GlnAsnArgArgGlyLeuAspLeuLeuPheTrpGluGlnGlyGly                                 151015                                                                        LeuCysLysAlaLeuGlnGluGlnCys                                                   20                                                                            (2) INFORMATION FOR SEQ ID NO:3:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 16                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:                                       AsnArgArgGlyLeuAspLeuLeuPheTrpGluGlnGlyGlyLeu                                 151015                                                                        Cys                                                                           (2) INFORMATION FOR SEQ ID NO:4:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 34                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:                                       AlaProProLeuLeuProHisSerAsnLeuAspHisIleLeuGlu                                 151015                                                                        ProSerIleProTrpLysSerLysLeuLeuThrLeuValGlnLeu                                 202530                                                                        ThrLeuGlnSer                                                                  (2) INFORMATION FOR SEQ ID NO:5:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 40                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:                                       SerSerThrProLeuLeuTyrProSerLeuAlaLeuProAlaPro                                 151015                                                                        HisLeuThrLeuProPheAsnTrpThrHisCysPheAspProGln                                 202530                                                                        IleGlnAlaIleValSerSerProCysHis                                                3540                                                                          (2) INFORMATION FOR SEQ ID NO:6:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 38                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:6:                                       CysPheAspProGlnIleGlnAlaIleValSerSerProCysHis                                 151015                                                                        AsnSerLeuIleLeuProProPheSerLeuSerProValProThr                                 202530                                                                        LeuGlySerArgSerArgArgAla                                                      35                                                                            (2) INFORMATION FOR SEQ ID NO:7:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 20                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION: SEQ ID NO:7:                                       GlyLeuAspLeuLeuPheTrpGluGlnGlyGlyLeuCysLysAla                                 151015                                                                        IleGlnGluGlnCys                                                               20                                                                            (2) INFORMATION FOR SEQ ID NO:8:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 24                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:8:                                        GlnAsnArgArgGlyLeuAspLeuLeuPheTrpGluGlnGlyGly                                 151015                                                                        LeuCysLysAlaIleGlnGluGlnCys                                                   20                                                                            (2) INFORMATION FOR SEQ ID NO:9:                                              (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 16                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:9:                                        AsnArgArgGlyLeuAspLeuLeuPheTrpGluGlnGlyGlyLeu                                 151015                                                                        Cys                                                                           (2) INFORMATION FOR SEQ ID NO:10:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 34                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:10:                                       SerProProLeuValHisAspSerAspLeuGluHisValLeuThr                                 151015                                                                        ProSerThrSerTrpThrThrLysIleLeuLysPheIleGlnLeu                                 202530                                                                        ThrLeuGlnSer                                                                  (2) INFORMATION FOR SEQ ID NO:11:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 30                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:11:                                       SerSerArgThrIleLeuPheProSerLeuAlaLeuProAlaPro                                 151015                                                                        ProSerGlnProArgLeuGlnAlaIleThrThrAspAsnCysAsn                                 202530                                                                        (2) INFORMATION FOR SEQ ID NO:12:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 37                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:12:                                       CysTyrGlnProArgLeuGlnAlaIleThrThrAspAsnCysAsn                                 151015                                                                        AsnSerIleIleLeuProProPheSerLeuAlaProValProLeu                                 202530                                                                        AlaThrArgArgArgArgAla                                                         35                                                                            (2) INFORMATION FOR SEQ ID NO:13:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 21                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:13:                                       ArgIleLeuAlaValGluArgTyrLeuLysAspGlnGlnLeuLeu                                 151015                                                                        GlyIleTrpGlyCysSer                                                            20                                                                            (2) INFORMATION FOR SEQ ID NO:14:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 19                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:14:                                       IleTrpGlyCysSerGlyLysLeuIleCysThrThrAlaValPro                                 151015                                                                        TrpAsnAlaSer                                                                  (2) INFORMATION FOR SEQ ID NO:15:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 11                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:15:                                       IleValArgMetTyrSerProThrSerIleLeu                                             1510                                                                          (2) INFORMATION FOR SEQ ID NO:16:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 16                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:16:                                       AspGlnAlaArgLeuAsnSerTrpGlyCysAlaPheArgGlnVal                                 151015                                                                        Cys                                                                           (2) INFORMATION FOR SEQ ID NO:17:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 28                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:17:                                       ProHisSerAsnLeuAspHisIleLeuGluProSerIleProTrp                                 151015                                                                        LysSerLysLeuLeuThrLeuValGlnThrLeuGlnSer                                       2025                                                                          (2) INFORMATION FOR SEQ ID NO:18:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 29                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:18:                                       HisAspSerAspLeuGluHisValLeuThrProSerThrSerTrp                                 151015                                                                        ThrThrLysIleLeuLysPheIleGlnLeuThrLeuGlnSer                                    2025                                                                          (2) INFORMATION FOR SEQ ID NO:19:                                             (i) SEQUENCE CHARACTERISTICS:                                                 (A) LENGTH: 21                                                                (B) TYPE: Amino acid                                                          (C) STRANDEDNESS: Single                                                      (D) TOPOLOGY: Unknown                                                         (ii) MOLECULE TYPE: Peptide                                                   (xi) SEQUENCE DESCRIPTION:SEQ ID NO:19:                                       AlaProProLeuLeuProHisSerAsnLeuAspHisIleLeuGly                                 151015                                                                        ProSerIleProTrpLys                                                            20                                                                            __________________________________________________________________________

What is claimed is:
 1. A peptide composition comprising a peptideselected from the group consisting:

    Y.sub.a -AA.sub.6 -AA.sub.21 -B.sub.a -Z                   (iv)

wherein Y_(a) is AA₁ -AA ₅ and B_(a) is AA₂₂ -AA₃₄ and AA₁ -AA₃₄ isAPPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS (SEQ ID NO:4) (IV), and Z is--OH or--NH₂ ; an analogue of the peptide having an amino acid sequence derivedfrom a strain/isolate of HTLV in a region corresponding to the peptide;a conjugate of the peptide or its analogue with carrier proteins; and apolymer of the peptide or its analogue.
 2. A peptide according to claim1 having the sequence:

    APPLLPHSNLDHILEPSIPWKSKLLTLVQLTLQS-Z (SEQ ID NO:4)         (IV).


3. An analogue of peptide (iv) according to claim 1 having the aminoacid sequence:

    Y.sub.a '-AA.sub.6 -AA.sub.21 -B.sub.a '-Z (x)

wherein Y_(a) ' is AA₁ -AA₅ and B_(a) ' is AA₂₂ -AA₃₄ ; AA₁ -AA₃₄ isSPPLVHDSDLEHVLTPSTSWTTKILKFIQLTLQS (SEQ ID NO:10) (X), and Z is --OH or--NH₂.